Field of the Invention
The present invention relates to a decoupler for damping the transmission of torque between a drive shaft of a motor vehicle and a belt pulley, with the aid of which rotational irregularities of the drive shaft can at least be damped, so that auxiliary assemblies connected to the belt pulley can be driven more uniformly by a drive means.
Description of the Related Art
From WO 2005/028899 A1, a crankshaft pulley decoupler for a motor vehicle is known, wherein a hub connected to a crankshaft of the motor vehicle has radially protruding lugs, which are coupled, through bow springs running in the circumferential direction, to a spring housing in which the bow springs are disposed. The spring housing is connected to a coil spring that encircles the spring housing radially outside, and which expands when there is an input of torque in the drive direction to bring about a frictional engagement with a belt pulley, in order to transmit the introduced torque to the pulley.
From DE 10 2009 004 713 A1, a pulley damper is known which has an input flange that is connectable to a drive shaft. Connected to the input flange through a free-wheel device is a torsional vibration damper, which is connected, in turn, directly to a belt pulley. The free-wheel device, which is situated between the input flange and the torsional vibration damper in the flow of force direction, has ramps bent up from a base plane, which make a free-wheel mechanism in the nature of a ratchet. In the push direction, an output disk of the free-wheel device can slide on the sloped flanks of the bent-up ramps, which moves the output disk axially without transmitting a torque from the input flange to the output flange. In the traction mode, the output disk can strike the tangentially backward-directed side of the bent-up ramp, and transmit a torque.
There is a constant need to refine decouplers so that unwanted torque transmission irregularities are avoided while noise emission is kept as low as possible.
An object of the present invention is to provide a decoupler with the aid of which unwanted torque transmission irregularities are avoided with negligible noise emission.